Utilization of Air Humidity and Surface Air Temperature Data in Regression Equations for Rainfall Forecast Simulation in the Gamping Area, Sleman, Yogyakarta (Yogyakarta Class 1 Geophysical Station)

Rainfall prediction simulations for January 2010 using predictors of air humidity (RH) and air temperature (T) have been carried out at Yogyakarta Geophysics Station. Rainfall prediction in January 2010 using average weather parameter data and real time data in the Gamping Sleman Yogyakarta area has been carried out using two regression methods, namely simple linear regression equation method and multiple linear regression. The evaluation is done by comparing and calculating the amount of deviation from the prediction of total monthly rainfall to the observation of total monthly rainfall. The results of data processing carried out to predict rainfall in January 2010 show. In the study area, rainfall was very strong with RMSE = 0.68 mm using predictors of air temperature and humidity at the same time.